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Full text of "Mosquitoes declared guilty sleeping sickness carriers."

18 Mosquito News 

WORLD-WIDE MOSQUITO CONTROL 

A recent news Item, dated November 19, 1941, 
Banpoon, Burma, carried an Interesting Item of 
news — "The fight against malaria — the worst 
natural enemy of efficiency on the Burma Road to 
China -- was given Impetus today by the arrival 
of two more members of the American anti-malaria 
mission. They were entomologist W. L. Jellison 
and engineer H. A. Johnson." (Note:— Mr. Johnson 
took charge of the Eastern Association Group while 
in Memphis. ) 

Mosquitoes Declared Guilty 
Sleeping Sickness Carriers 

Washington (U.P.) — "One of the most baffling 
mysteries of medical science was believed solved 
last nlaht with a government announcement that mo- 
sauitoes carry sleeping sickness. 

For almost 20 years federal, state and local 
health authorities have sought the carrier of the 
disease that kills from 250 to 500 persons and hun- 
dreds of animals each year. Until now every clue 
was worthless. 

The mosquito ha.s been convicted of many of- 
fenses. He is a carrier of malaria, yellow fever, 
dengue and other maladies. 

Scientists long have suspected him of compli- 
city in the spread of encephalomyelitis (sleeping 
sickness). But they never could prove It. Now 
they claim conclusive proof. 



Mosquito News 19 



In a wholesale roundup of "suspects" the Bur- 
eau of Entomology and Plant Quarantine, cooperat- 
ing with the University of California and Washing- 
ton state and local .health authorities collected 
about 10,000 mosquitoes, files and other biting 
Insects. The collection was made In the Yakima 
Valley of Washington during the summer of 1940 
when 27 humans and 40 to 50 unvacclnated horses 
had sleeping sickness. 

The Insects were Identical, frozen and ship- 
ped In dry Ice to the University of California 
laboratory at San Francisco. Then they were divid- 
ed into lots or "pools" according to family and 
species, washed, ground and the serum Injected In- 
to mice. 

One pool composed of culex tarsalls mosquitoes 
produced symptoms of the St. Louis type of sleep- 
ing sickness. That type received its name from 
the severe epidemic which took more than 100 lives 
in St. Louis during the summer of 1932. 

That was the criminal medical scientists were 
after. At last they had definite proof of his 
guilt. 

It had been demonstrated previously that 
mosquitoes could transmit the disease under labor- 
atory conditions. But that did not prove that 
they were the actual carriers of the disease. This 
was the first definite proof that mosquitoes col- 
lected in the field were the actual carriers. 

Medical authorities said the particular spe- 
cies of mosquito found carrying the virus Is wide- 
spread in states west of the Mississippi. ""he 



20 Mosquito News 



same kind of mosquitoes, placed In a different "pool" 
were found to cause sleeping sickness In horses. 

Last year, according to public health service 
records, there were more than 3,000 cases of human 
sleeping sickness in the United States. About nine 
per cent of the cases were fatal, the records showed. 

The findings, while of great scientific Import- 
ance, leave some questions unanswered, the Bureau of 
Entomology and Plant Quarantine said. The scientists 
now want to know whether: 

(1) Mosquitoes are the only transmitting agents 
of human encephalo; (2) whether the culex tarsalls 
mosquito is the only type transmitting the disease; 
(3) whether mosquitoes must be abundant to cause the 
disease, and (4) whether mosquitoes harbor the 
disease between outbreaks. 

If these facts are established, a plan for 
mosquito eradication can be mapped that might con- 
trol sleeping sickness as effectively as mosquito 
eradication helped control yellow fever. » 

Newark Sunday Ledger 
November 9, 1941 



Hailed On Gains In Malaria War 

St. Louis (A. P. ) — "A young Iowa-born scien- 
tist received medicine's highest honors today for 
helping to make the tropics habitable for troops. 

The American Society of Tropical Medicine pre- 
sented to Dr. Lloyd E. Rozeboom of Johns Hopkins